TIP: The RIGHT OUTER JOIN and FULL OUTER JOIN are. There are different types of SQLite joins: INNER JOIN (or sometimes called simple join) LEFT OUTER JOIN (or sometimes called LEFT JOIN) CROSS JOIN. A SQLite JOIN is performed whenever two or more tables are joined in a SQL statement. A Right Outer Join will do just the opposite. SQLite JOINS are used to retrieve data from multiple tables. A Left Outer Join will return all the rows from table 1 and only those rows from table 2 which are common to table 1 as well. all the records that are common between table 1 and table 2. select * from a FULL OUTER JOIN b on a.a = b. An Inner Join will return the common area between these tables (the green shaded area in the diagram above) i.e. If something in A doesn't have a corresponding datum in B, then the B portion is null, and vice versa. Select a.*, b.* from a,b where a.a(+) = b.b Ī full outer join will give you the union of A and B, i.e. The SQLite INNER JOIN keyword (or sometimes called simple JOIN) is used to combine column values of two tables and returns all rows from both of the tables. select * from a RIGHT OUTER JOIN b on a.a = b.b Select a.*, b.* from a,b where a.a = b.b(+) Ī right outer join will give all rows in B, plus any common rows in A. select * from a LEFT OUTER JOIN b on a.a = b.b Select a.*, b.* from a,b where a.a = b.b Ī left outer join will give all rows in A, plus any common rows in B. select * from a INNER JOIN b on a.a = b.b Note that (1,2) are unique to A, (3,4) are common, and (5,6) are unique to B.Īn inner join using either of the equivalent queries gives the intersection of the two tables, i.e. Suppose you have two tables, with a single column each, and data as follows: A B the inner part of a Venn diagram intersection.Īn outer join of A and B gives the results of A union B, i.e. SELECT pets.name AS petname, owners.name AS owner FROM pets FULL JOIN owners ON pets.ownerid owners.id The resulting table is again different in this instance all rows from the two tables are kept.
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